Fragile X Syndrome

Important

It is possible that the main title of the report Fragile X Syndrome is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.

Synonyms

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• Fragile Site, Folic Acid Type, Rare, Fra(X)(Q27.3)
• Marker X Syndrome
• Martin-Bell Syndrome
• X-linked Mental Retardation and Macroorchidism
• Fragile X Mental Retardation Protein, FMRP
• Fragile X Mental Retardation Syndrome
• Mental Retardation, X-Linked, Associated With Mar Xq28

Disorder Subdivisions

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• None

General Discussion

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Fragile X syndrome is characterized by moderate mental retardation in affected males and mild mental retardation in affected females. Distinctive physical features are sometimes present in affected males including a large head, long face, prominent forehead and chin, protruding ears, loose joints and large testes, but these features develop over time and may not be obvious until puberty. Motor and language delays are usually present but also become more apparent over time. Behavioral abnormalities including autistic behaviors are common.



Fragile X syndrome is caused by an abnormality (mutation) in the FMR1 gene. Affected individuals have an increased number of copies of a portion of the gene called CGG repeats. The greater the number of copies of CGG, the more likely the increased severity of the disorder. Fragile X syndrome occurs more often in males and results in more severe disease in males.



Mutations in the FMR1 gene are associated with two other conditions in addition to the fragile X syndrome (FXTAS and POF) and these conditions have been termed FMR1-Related Disorders. (See the Related Disorders section of this report for brief summaries of the other disorders.)

Resources

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The Arc (a national organization on mental retardation)

1010 Wayne Ave

Suite 650

Silver Spring, MD 20910

Tel: (301)565-3842

Fax: (301)565-3843

Tel: (800)433-5255

TDD: (817)277-0553

Email: info@thearc.org

Internet: http://www.thearc.org/



FRAXA Research Foundation

45 Pleasant Street

Newburyport, MA 01950

USA

Tel: 9784621866

Fax: 9784639985

Email: info@fraxa.org

Internet: http://www.fraxa.org



National Fragile X Foundation

PO Box 190488

San Francisco, CA 94119

USA

Tel: 9259389300

Fax: 9259389315

Tel: 8006888765

Email: NATLFX@FragileX.org

Internet: http://www.FragileX.org



New York State Institute for Basic Research in Developmental Disabilities

1050 Forest Hill Road

Staten Island, NY 10314

Tel: (718)494-0600

Fax: (718)698-3803

TDD: (718)494-5117

Email: vietcoat@ix.netcom.com



NIH/National Institute on Aging

PO Box 8057

Gaithersburg, MD 20892-8057

Tel: (301)496-1752

Tel: (800)222-2225

Internet: http://www.nih.gov/nia



Simon, Valerie, M.D.

Kennedy-Krieger Institute

Behavioral Genetics Unit

Room 103

707 North Broadway Avenue

Baltimore, MD 21205

Tel: (301)550-9321



NIH/National Institute of Child Health and Human Development

31 Center Dr

Building 31, Room 2A32

MSC2425

Bethesda, MD 20892

Tel: (301)496-5133

Fax: (301)496-7101

Internet: http://www.nih.gov/hichd/



New Horizons Un-Limited, Inc.

811 East Wisconsin Ave

Suite 937

Milwaukee, WI 53202

USA

Tel: 4142990124

Fax: 4143471977

Email: horizons@new-horizons.org

Internet: http://www.new-horizons.org



Let Them Hear Foundation

1900 University Ave #101

East Palo Alto, CA 94303

Tel: (650)462-3143

Fax: (650)462-3143

Tel: (877)735-2929

Email: info@letthemhear.org

Internet: http://www.letthemhear.org



Fragile X Society

Road End House

6 Stortford Road

Great Dunmow, Essex, CM6 1DA

UK

Tel: 01371 875100

Fax: 01371 859915

Email: info@fragilex.org.uk

Internet: http://www.fragilex.org.uk

For a Complete Report

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This is an abstract of a report from the National Organization for Rare Disorders, Inc. ® (NORD). A copy of the complete report can be obtained for a small fee by visiting the NORD website. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational treatments (if available), and references from medical literature. For a full-text version of this topic, see http://www.rarediseases.org/search/rdblist.html

The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report.

This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site www.rarediseases.org or email orphan@rarediseases.org

Last Updated:   8/9/2006

Copyright   1988, 1989, 1990, 1991, 1994, 1995, 1997, 1998, 1999, 2006 National Organization for Rare Disorders, Inc.